Generally, an inductor is a passive electrical component that can store energy in a magnetic field created by an electric current passing through it. An inductor may be constructed as a coil of conductive material wrapped around a core of dielectric or magnetic material. One parameter of an inductor that may be measured is the inductor's ability to store magnetic energy, also known as the inductor's inductance. Another parameter that may be measured is the inductor's Quality (Q) factor. The Q factor of an inductor is a measure of the inductor's efficiency and may be calculated as the ratio of the inductor's inductive reactance to the inductor's resistance at a given frequency.
Traditionally, inductors are used as discrete components which are placed on a substrate such as a printed circuit board (PCB) and connected to other parts of the system, such as an integrated circuit (IC) chip, via contact pads and conductive traces. Discrete inductors are bulky, require larger footprints on the PCB, and consume lots of power. Due to the continued miniaturization of electric devices, it is desirable to integrate inductors into IC chips. Therefore, there is a need for manufacturing integrated inductors that provide the benefit of size, cost and power reduction without sacrificing the electrical performance.